By Steve Almasy, CNN The US Coast Guard thinks the environmental impact from an overturned cargo ship along the Georgia coast is limited so far, Cdr. Norm Witt said Tuesday.

Tuesday, September 10th 2019, 6:09 PM EDT

Updated:

Tuesday, September 10th 2019, 6:39 PM EDT

By Steve Almasy, CNN

The US Coast Guard thinks the environmental impact from an overturned cargo ship along the Georgia coast is limited so far, Cdr. Norm Witt said Tuesday.

"We don't have any indications at this point that we have a major release" from the 656-foot Golden Ray that capsized in St. Simons Sound, Witt told reporters. Everyone is safe after rescuers saved the final four men trapped on the ship on Monday.

He said spill management crews have used booms as part of a pollution mitigation effort and are trying to retrieve fuel and oil that has come from the ship that was set to haul 4,200 vehicles to Baltimore. They are also trying to seal fuel vents, where fuel can escape now that the ship is on its side.

"I can't tell you that there won't be any pollution. There is pollution as of right now. It's limited in scope," he said.

CNN reached out to several environmental groups in the area, and they all said it was too early to tell what impact the spill has had.

Monday, Chris Graff, the director of response services for a spill management company, said the oil -- which officials described as a light sheen -- was possibly from hydraulic fuel from the engine.

"We know that there's manatees in the area, there's turtle nesting areas in the area, there's some bird activity in the area. All of these are concerns for us," said Graff, of Gallagher Marine Systems.

Witt acknowledged it will be weeks, perhaps months, before the 71,000-ton Golden Ray is moved from the scene. Plans for how to salvage the ship have not been finalized, he said.

Witt also said officials hope to reopen the shipping channel on Thursday, though it likely will be one-way traffic and only during limited hours. And the Thursday target is very aggressive, he said.